Division of Intramural Population Health Research -Gestational diabetes mellitus (GDM) , impaired glucose intolerance during pregnancy, may cause increased risk for type 2 diabetes , and comorbidities such as cardiovascular disease (CVD), and certain cancers. This study 1) investigates the genetic factors and enviromental risk , 2) understand molecular mechanism. A secondary goal is to collect baseline information of childrn born from pregnancies complicated by glucose intolerance. Data collection is from the Diabetes & Women's Health (DWH) Study as well as the Nurses' Health Study II and the Danish National Birth Cohort (DNBC).